What is a good algorithm for pitch shifting?

Question

I have an algorithm in place that works for audio files, but I'm trying to apply it to frames to achieve an auto tune type of effect. It shifts the pitch but makes it sound broken up or like it's skipping when I apply it to the individual frames from an audioworklet. This is essentially the algorithm in c#. I converted it to typescript to use it with WebAssembly. I'm at a loss as to why the output sounds great on a full audio file, but broken up or like it's skipping when I apply it to individual frames. Any advice would be greatly appreciated.